Sleep, the activity we spend one third of our lives doing, has been found to provide a time when the brain’s synapses rest and prepare for the next day so they can be strong and receive new input.

This reset of the brain in known as “synaptic homeostatsis” and is needed so brains do not become overloaded and burn out.

Study co-author Dr Chiara Cirelli of the University of Wisconsin-Madison Center for Sleep and Consciousness, said: “Sleep is the perfect time to allow the synaptic renormalisation to occur because when we are awake, we are 'slaves' of the here and now, always attending some stimuli and learning something.

Sleep expert Dr Nerina Ramlakhan joined Ruth and Eamonn on Monday's This Morning to discuss sleep struggles and night terrors.

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Sleep expert Dr Nerina Ramlakhan joined This Morning hosts Ruth and Eamonn to give her advice to viewers who struggle every night to get the rest they need

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Sleep is required for us to store more information

During sleep, we are much less preoccupied by the external world and the brain can assess all our synapses, and renormalise them in a smart way

Dr Chiara Cirelli

“During sleep, we are much less preoccupied by the external world and the brain can assess all our synapses, and renormalise them in a smart way.”

The scientists have direct evidence of this Synaptic Homeostasis Hypothesis after investigating the shrinking of synapses in mice while they slept.

The researchers said that sleep is what people must do in order to continue to learn new things and is needed for the consolidation of memories.

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Scientists tested out their theories on mice

The papers published by journal Science also offer evidence that we sleep to forget some of the things we learn each day and sleep deprivation stops the brain’s ability to form new memories.

Russell Foster, who directs the Sleep and Circadian Neuroscience Institute at the University of Oxford, said: “It is critical to have pruning back at night, so that the huge amount of information encoded by temporary synapses during the day won't overwhelm the brain.”

The scientists say sleep is a restorative time when people replace and rebuild parts of the brain that was burned up throughout the day.

Synapses are constantly strengthening during the day so the brain can soak up new experiences.

When the body sleeps, it takes advantage of the decreased brain activity that occurs.